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Is there a possible way of doing this within comfigurator? Yet I still want it to receive the time update from other modules (etc CBus)
Shah
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Do you mean stop broadcastting the time to Cbus?
I dont think it can be done, but why do you need to do this?
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Cbus timing works on a priority basis, some Cbus devices broadcast their times at different intervals. The logic behind this is that a more accurate device will broadcast it\'s time more frequently. When a device on the Cbus network \'sees\' a time broadcast it will yield to that device. This means a device, which is more accurate, will transmit more regularly and eventually all devices on the Cbus network will yield control to this one device.
The question is not wheather Comfort can stop transmitting time but that they do conform to this yielding process. Currently, and as far as I can figure out, the most frequent Cbus brodcast is every 60 minutes for their most accurate devices. Comfort also sends time updates every 60 minutes but it never yields to the Cbus unit sending time.
What would be nice is if Comfort had a setting that could influence the time broadcast. Either a Fast/Slow setting predetermined in the firmware. The Fast setting could be the current 60 minutes and the slow setting could be 90 minutes. The next step is to then yield the time broadcasts to a device that has a higher priority EG if the Cbus device sends every 60 minutes then Comfort needs to accept this time and not broadcast it\'s own. If the Cbus broadcasts are every 90 minutes then Comfort will take over as the Time Master and broadcast time back to Cbus at 60 minute intervals.
This is all well documented in the Time&Date application over on the Cbus Forum.
Regards,
Ingo
PS. Let me do some ComfortClient marketing. I currently use the ComfortClient software which keeps Comfort in sync with my PC on a regular basis. My PC is in sync via NTP so it\'s the best time source on the network. If Comfort drifts more than 5s from my PC time it\'s corrected automatically. Maybe that is an option for you as well.
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I wonder if any Cbus devices actually follow this updating policy
How do the devices know how accurate they are with respect to all other cbus devices? There is no spec that if the accuracy is 20 ppm then update every 50 minutes, 25 ppm update every 30 minutes etc so how would the devuices know how often to update
Also the time can be updated automatically as well as manually
Lets say a cbus device updates every 30 minutes but Comfort updates every 60 seconds because it is less accurate
Someone changes the time manually on Comfort 10 minutes after the last update which updates the time on cbus Then all devices think that this is the most accurate clock and would cease to update.
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07-03-2010, 07:14 AM
(This post was last modified: 07-03-2010, 07:47 AM by Ingo.)
They actually do, I noticed this when logging some CGate messages in PICED and saw on a Comfort startup I get a message in PICED stating that it relinquish control to Comfort\'s broadcast.
The descision on who is more accurate than the other is purely a hardcoded method. HomeGate is more accurate than a PAC for instance. Clipsal makes some assumtions that HomeGate running on a PC is probably NTP sync\'d and a PAC is running of it\'s internal clock. A good description is in the PICED/HomeGate help file.
Yes, once someone changes the time manually then that device will probably become the Master at that time, further updates from that point will probably follow the broadcast interval again and whoever is more frequent will eventually be selected as the Master again. If I however set time manually, say every 10 minutes, on a unit then it stands to reason that I will be the time master until I stop updating the time manually.
On the otherhand, even if Comfort keeps on sending time it doesn\'t really matter because Comfort accepted time from the more acurate time source anyway. The problem with this is that 60 minutes is also the shortest interval from the Cbus side so it would have relinquished control to Comfort and NOT update time anymore. Comfort would end up being the only time source. If Cbus had something that sent more frequently than 60 minutes then all would be ok. Saying this, with two devices sending at the same interval it is just fate who will be the time master at that point in time, it probably depends on who starts-up first on a reboot - who knows.
Ingo
